Technology Improvement does not necessarily improve people's situation in rural areas of developing countries. Arsenic contamination of underground water in Bangladesh is one of the cases. They have been suffering from arsenic disaster of drinking water since 1993. Various alternative technologies were introduced to supply safe drinking water since arsenic contamination was discovered. However, the technologies were not necessarily accepted by local residents. Many inhabitants carry water everyday from safe water sources which are sometimes far from their houses. Otherwise, they continue to drink arsenic contaminated water of the wells which are located close to their residences even though they know the water is arsenic contaminated. Here, we can recognize the arsenic contamination problem in Bangladesh as the disaster which is deeply related with local people's social environment. Paying attention to the relation between the disaster and local social environment in Bangladesh, the methodology on evaluation and introducing process of water resources alternatives for mitigating arsenic contamination disaster on drinking water is presented. In the study, local residents' behavior about water resources selection is in particular focused on. Two models are introduced to describe their behavior; one is for evaluating people's psychological stress of carrying water and the other is for evaluating people's capability to get safe water. The two models are combined and the function of evaluating local people's behavior on water resources selection is developed. With this function, the place where the alternative should be introduced and the type of alternative which are preferable for considered local people can be analyzed. JEL Classification: I32, Q01, C72